Logic Masters Deutschland e.V.

This puzzle is the second puzzle in a loop series that uses thermometer clues. A link to the previous puzzle in the series is given below.
Heated Whisper Loop

Rules:

Normal Sudoku rules apply: Place the digits 1 to 9 in every row, column, and 3x3 box.

Along thermometers, digits must strictly increase from the bulb to the tip.

Draw a one-cell-wide loop of orthogonally connected cells. The loop may not touch itself, not even diagonally.

-- All thermometer bulbs must be on the loop.

-- The digit in a thermometer bulb gives the total number of loop cells in the 3x3 Sudoku box containing the bulb.

-- The loop acts as a Dutch Whispers line (i.e., adjacent digits on the loop must have a difference of at least 4).